Astronomy Notes / Life cycle of stars

 Astronomy Notes / Life cycle of stars



 Astronomy Notes / Life cycle of stars

LIFE CYCLE OF STARS

·         Proto Star

*      Formed by compression of galactic gas and dust which causes Nuclear Fusion, emitting large amount of heat and light

·         Red Giants

*      Continued Nuclear Fusion over a period of time result in depletion of hydrogen and the helium core becomes increasingly heavy, resulting into swelling and reddening of outer regions

*      Stars of gigantic dimensions are termed as Red Giants

·         Novae & Supernovae

*      Stars whose brightness increase suddenly by ten to twenty magnitudes or more due to partial or outright explosion in the star

*      When brightness increases to 20 magnitudes or more - supernovae

·         White Dwarfs

*      A novae or Supernovae explosion in a star like our Sun may leave behind a very dense core of that star

*      A star of this size cools and contracts to become a White Dwarf

·         Neutron Star

*      A Supernovae explosion in a star bigger than the Sun may leave behind an extremely dense, residual core of that star

·         Pulsar

*      The extremely dense core left after the explosion of a bigger star: neutron star

*      Because of their small size, neutron stars spin very fast and while spinning, radiate all kinds of electro-magnetic radiations – Pulsar

*      Jocelyn Bell discovered the first pulsar in 1967

·         Black Holes

*      Stars having mass greater than three times that of the sun, have contracted so much because of their great gravitational power and have developed super density

*      It is so dense that nothing, not even light can escape from its gravity and hence called Black hole

·         Fixed stars

*      Stars which do not appear to alter their relative positions in the sky. They are called dog stars

·         Binary stars

*      Group of two stars revolving round each other under mutual gravitational attraction

·         Temporary stars

*      Those who suddenly flare up to a greatly increased brightness and fade away after a short time. They are called novae

·         Variable stars

*      Stars are brightness of which varies from time to time


 Astronomy Notes / Life cycle of stars

Comments

Post a Comment

Popular posts from this blog

Renaissance Leaders of Kerala / Poikayil Yohannan (Kumara Guru) / PSC Notes / Education Notes

Image
  POIKAYIL YOHANNAN (KUMARA GURU) Poykayil Yohannan (Eraviperoor, 17 February 1878-1939), known as Poikayil Appachan to his followers, or Kumara Gurudevan. He was a Dalit activist, poet, Christian preacher and the founder of the socio-religious movement Prathyaksha Raksha Daiva Sabha ("God's Church of Visible Salvation"). He bought 125 acres of land in different parts of Travancore for the use of PRDS. The new organization was headquartered at Eraviperoor. Poikayil Yohannan set up schools and industrial training centers in different places in addition to constructing buildings for religious ceremonies and public functions. Poikayil Yohannan was also a member of the Dalit advocacy group Sadhujana Paripalana Sangham (SJPS) which has been founded in 1905 by another Dalit leader of Kerala, Ayyankali.  Yohannan was also twice nominated, in the years 1921 and 1931, to the Sree Moolam Praja Sabha, the legislative council of the princely state of Travancore.
Read more

Information Technology & Cyber Laws Notes / Kerala PSC Helper / Cyber Space / Cyber crimes

CYBER LAW OF INDIA Cyber Law is the law governing cyber space. Cyber space is a very wide term and includes computers, networks, software, data storage devices (such as hard disks, USB disks etc..) the Internet, websites, emails and even electronic devices such as cell phones, ATM machines etc... Cyber law encompasses laws relating to : Cyber crimes Electronic and Digital Signatures Intellectual Property Data Protection and Privacy Cyber Crimes Cyber crimes are unlawful acts where the computer is used either as a tool or a target or both. The enormous growth in electronic commerce (e-commerce) and online share trading has led to a phenomenal spurt in incidents of cyber crime. Cyber crimes can involve criminal activities that are traditional in nature, such as theft, fraud, forgery, defamation and mischief, all of which are subject to the Indian Penal code. The Computer as a Target : using a computer to attack other computers.  Ex: Hacking, Virus/Worm attacks, DOS attack etc.... The...
Read more

Renaissance Leaders of Kerala / Vagbhatananda Gurudevar/ PSC Helper/Education Notes

Image
  VAGBHATANANDA GURUDEVAR Vagbhatananda Gurudevar, was a disciple of Sree Narayana Guru He was born in a Thiyya family of North Malabar of a famous Kalari warrior and trainer, Kochu Gurukkal. After becoming the disciple of Sree Narayana Guru, guru asked him to concentrate on Malabar areas to remove social discriminations prevalent in the area and to work for the poor. He formed an organization Uralungal Koolivelakkarude Paraspara Sahayya Sangham to fight the caste barriers and unemployment plaguing the region. Unlike Narayana Guru, he disapproved of idol worship. The spiritual lectures he delivered across the length and breadth of Kerala gave him the title Vagbhatananda. He formed the Atma Vidya Sangham for the spiritual reformation of the people.
Read more